You need to using the screwdriver, remove 4 screws from the back, to open the cover back of the multimeter, then take the insulation strip before using it.
 

          
Introduction
This meter is a compact 3 5/6-digit digital multimeter for measuring DC and AC voltage, resistance, frequency,capacitance and continuity.
In addition, non-contact AC voltage detection function is also provided. The meter is operated through a key.

In Auto Check mode, the meter automatically selects measurement function of DC voltage,AC voltage,or resistance based on the input

via the test leads.It features small size and lightness, and it is easy to operate.
 

Feature
1)Display:3 5/6-digit LCD, with a max reading of 5999
2)Overrange indication: " OL " shown on the display 3)Negative Polarity Indication:Negative sign "-"shown on the display automatically
4)Sampling Rate:About 2 to 3 times/sec
5)Battery:1.5V button cell,LR44 or equivalent,2 pieces
6)Operation Environment: Temperature:0-40 degree, Relative humilty:7)Storage Temperature: Temperature: -10-50 degree,Relative humilty:8)Operating Altitude: 0 to 2000 meters
 

Specifications

DC Voltage:
Range Resolution Accuracy
6V 0.001V ±(0.8%+3)
60V 0.01V ±(0.8%+3)
600V 0.1V ±(0.8%+3)
250V 1V ±(0.8%+3)
Input Impedance:10MΩ
Max.Allowable Input Voltage:600V

AC Voltage:
Range Resolution Accuracy
6V 0.001V ±(1.0%+5)
60V 0.01V ±(1.0%+5)
600V 0.1V ±(1.0%+5)
Input Impendace:About 10MΩ
Frequency Range:40Hz to 400Hz
Max.Allowable Input Voltage:600V
Responable:Average.calibrated in rms of sine wave

Resistance:
Range Resolution Accuracy
600Ω 0.1Ω ±(2.0%+10)
6kΩ 0.001kΩ ±(1.2%+6)
60kΩ 0.01kΩ ±(1.0%+4)
600kΩ 0.1kΩ ±(1.0%+4)
6MΩ 0.001MΩ ±(2.0%+4)
10MΩ 0.01MΩ ±(2.0%+4)

Diode and Continuity:YES
Frequency:
Range Resolution Accuracy
10Hz 0.001Hz ±(1.0%+4)
100Hz 0.01Hz ±(1.0%+4)
1KHz 0.1Hz ±(1.0%+4)
10KHz 0.001KHz ±(1.0%+4)
100KHz 0.01KHz ±(1.0%+4)
Input Voltage:1V rms -20V rms
Measurement Range:1Hz - 100kHz

Capacitance:
Range Resolution Accuracy
40nF 0.01nF ±(4.0%+5)
400nF 0.1nF ±(4.0%+5)
4μF 0.001μF ±(4.0%+5)
40μF 0.01μF ±(4.0%+5)
100μF 0.01μF ±(5.0%+5)
Measurement Range: 1nF-100μF

Non-contact AC Voltage Detection
Detection Range: 50V-600V
Frequency Response: 50Hz/60Hz

Automatic Power-Off:Yes

 GK4 Voltage Tester